Top of the pill pops
Lipitor, Pfizer's cholesterol drug, was the best-selling drug for the fifth year in a row in 2005, achieving worldwide sales of US$12.2bn.
Lipitor, Pfizer's cholesterol drug, was the best-selling drug for the fifth year in a row in 2005, achieving worldwide sales of US$12.2bn.
Coming in at numbers two and three were Sanofi-Aventis' Plavix, an antiplatelet medication, with $6.3bn and GlaxoSmithKline's asthma treatment Advair with $5.5bn.
According to data compiled by Bloomberg, the trend in the 25 top-selling medicines last year was that they targeted persistent illnesses, such as high-cholesterol, stomach ulcers and depression. Analysts have put this down to big marketing spends on such drugs in the face of pending patent expirations, the most notable being Merck & Co.'s cholesterol treatment Zocor, which came in sixth with $4.4bn but loses patent protection in the US in June.
Pfizer's high blood pressure treatment Norvasc was fourth with $4.7bn and AstraZeneca's ulcer treatment Nexium was fifth following a 19% rise in sales to £4.6bn.
Wood Mackenzie Consultants estimates that $21bn of US sales will be lost to patent expiration in 2006 and 2007, and that products with another $29.5 billion in revenue, such as Merck's osteoporosis treatment Fosamax, will be threatened by patent challenges from generic drugmakers.
'Pfizer, in particular, is really going to suffer,' said Martyn Link, a senior life sciences analyst at Wood Mackenzie. 'In 2004 it had five drugs in the top 25, in 2009 it'll only have one.'
The introduction of a cheaper generic drug can cut sales of a branded medicine by as much as 70%, as demonstrated by Pfizer's epilepsy treatment Neurontin, whose revenue plummeted by around 76% from $2.7bn in 2004 to $639m in 2005 in the face of generic competition.
Amgen was the only biotechnology company in the top 25. Its anemia treatment Aranesp reined in $3.3bn and came in at 14th. In 2004 it ranked 22nd with sales of $2.5bn.
Drugs made by biotechnology processes aren't as vulnerable to generic competition as EU and US regulators have not yet decided upon an approval process. Other biotech drugs are thus expected to enter the top 25 in the coming years.
European companies hold only three of the top 10 spots, but their products 'tend to have stronger patent protection than [those of] American drugmakers', according to analysts. No producst from Asian companies made the top 25, but Wood Mackenzie is forecasting that Takeda Pharmaceutical of Osaka, Japan will make the grade in 2009 with its oral diabetes drug Actos.